From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932771Ab3BYWVZ (ORCPT ); Mon, 25 Feb 2013 17:21:25 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:55338 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932421Ab3BYWUh (ORCPT ); Mon, 25 Feb 2013 17:20:37 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "David S. Miller" Subject: [ 56/58] sparc64: Handle hugepage TSB being NULL. Date: Mon, 25 Feb 2013 14:19:52 -0800 Message-Id: <20130225221648.317896578@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130225221636.018756060@linuxfoundation.org> References: <20130225221636.018756060@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: "David S. Miller" [ Upstream commit bcd896bae0166b4443503482a26ecf84d9ba60ab ] Accomodate the possibility that the TSB might be NULL at the point that update_mmu_cache() is invoked. This is necessary because we will sometimes need to defer the TSB allocation to the first fault that happens in the 'mm'. Seperate out the hugepage PTE test into a seperate function so that the logic is clearer. Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- arch/sparc/mm/init_64.c | 38 ++++++++++++++++++++++---------------- 1 file changed, 22 insertions(+), 16 deletions(-) --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -314,16 +314,31 @@ static void __update_mmu_tsb_insert(stru struct tsb *tsb = mm->context.tsb_block[tsb_index].tsb; unsigned long tag; + if (unlikely(!tsb)) + return; + tsb += ((address >> tsb_hash_shift) & (mm->context.tsb_block[tsb_index].tsb_nentries - 1UL)); tag = (address >> 22UL); tsb_insert(tsb, tag, tte); } +#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE) +static inline bool is_hugetlb_pte(pte_t pte) +{ + if ((tlb_type == hypervisor && + (pte_val(pte) & _PAGE_SZALL_4V) == _PAGE_SZHUGE_4V) || + (tlb_type != hypervisor && + (pte_val(pte) & _PAGE_SZALL_4U) == _PAGE_SZHUGE_4U)) + return true; + return false; +} +#endif + void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) { - unsigned long tsb_index, tsb_hash_shift, flags; struct mm_struct *mm; + unsigned long flags; pte_t pte = *ptep; if (tlb_type != hypervisor) { @@ -335,25 +350,16 @@ void update_mmu_cache(struct vm_area_str mm = vma->vm_mm; - tsb_index = MM_TSB_BASE; - tsb_hash_shift = PAGE_SHIFT; - spin_lock_irqsave(&mm->context.lock, flags); #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE) - if (mm->context.tsb_block[MM_TSB_HUGE].tsb != NULL) { - if ((tlb_type == hypervisor && - (pte_val(pte) & _PAGE_SZALL_4V) == _PAGE_SZHUGE_4V) || - (tlb_type != hypervisor && - (pte_val(pte) & _PAGE_SZALL_4U) == _PAGE_SZHUGE_4U)) { - tsb_index = MM_TSB_HUGE; - tsb_hash_shift = HPAGE_SHIFT; - } - } + if (mm->context.huge_pte_count && is_hugetlb_pte(pte)) + __update_mmu_tsb_insert(mm, MM_TSB_HUGE, HPAGE_SHIFT, + address, pte_val(pte)); + else #endif - - __update_mmu_tsb_insert(mm, tsb_index, tsb_hash_shift, - address, pte_val(pte)); + __update_mmu_tsb_insert(mm, MM_TSB_BASE, PAGE_SHIFT, + address, pte_val(pte)); spin_unlock_irqrestore(&mm->context.lock, flags); }